1. Technical Field
The present invention concerns a fill electronic switching system, and more particularly an X.25 network connection for enabling X.25 protocol communication for a fill electronic switching system.
2. Related Art
A full electronic switching system is connected with an external X.25 protocol conversion unit by means of an IPC (Inter Process Communication) or LAN (Local Area Network) in order to communicate with an X.25 network through a single connection port. The IPC or LAN format of the data from the switching system is converted into the X.25 protocol format by the X.25 conversion unit so as to be transferred to the external X.25 network. Conversely, the X.25 protocol format from the external X.25 network is converted into the IPC or LAN format so as to be transferred to the switching system.
However, such external X.25 protocol conversion unit complicates the full electronic switching system because of additional connections cables and devices, thus increasing the cost. Moreover, since the data format conversion is made outside the switching system, any error occurring in the operation of the X.25 protocol conversion unit may risk loss of the transferred data or link breakage. The single connection port for communicating with the X.25 network requires that the switching system be further provided with a plurality of additional X.25 protocol conversion units in order to provide multiple connections with the X.25 network.
The following patents are considered to be representative of the prior art, and are burdened by the disadvantages set forth herein: U.S. Pat. No. 5,001,704 to Narup et al., entitled Multipurpose Bus Interface, U.S. Pat. No. 5,218,602 to Grant et al., entitled Interprocessor Switching Network, U.S. Pat. No. 5,490,252 to Macera et al., entitled System Having Central Processor For Transmitting Generic Packets To Another Processor To Be Altered And Transmitting Altered Packets Back To Central Processor For Routing, U.S. Pat. No. 5,363,369 to Hemmady et al., entitled System For Inter Packet Community Communication, U.S. Pat. No. 5,502,718 to Lane et al., entitled Device For Switching High Speed Protocol Units, And Corresponding Switching Procedure, U.S. Pat. No. 5,533,017 to Thor, entitled Line Interface Device For Fast-Packet Switching Network, U.S. Pat. No. 5,568,471 to Hershey et al., entitled System And Method For A Workstation Monitoring And Control Of Multiple Networks Having Different Protocols, U.S. Pat. No. 5,592,622 to Isfeld et al., entitled Network Intermediate System With Message Passing Architecture, U.S. Pat. No. 5,634,015 to Chang et al., entitled Generic High Bandwidth Adapter Providing Data Communications Between Diverse Communication Networks And Computer system, U.S. Pat. No. 5,659,684 to Giovannoni et al., entitled Methods And Apparatus for Interconnecting Personal Computers (PCA) And Local Area Networks (LANS) Using Packet Protocols Transmitted Over A Digital Data Service (DDS), U.S. Pat. No. 5,691,985 to Lorenz et al., entitled System And Method For Increasing Throughput Of Inter-Network Gateways Using A Hardware Assist Engine, U.S. Pat. No. 5,727,149 to Hirata et al., entitled Network Interface Apparatus And Data Transmission Control Method Thereof, U.S. Pat. No. 5,740,174 to Somer, entitled Method And apparatus For Performing Collision Detection And Arbitration Within An Expansion Bus Having Multiple Transmission Repeater Units, and U.S. Pat. No. 5,751,951 to Osborne et al., entitled Network Interface.